What is a double-storey extension?

A double-storey extension (also called a two-storey extension) adds rooms on both the ground and first floor in one build. It typically gives a larger kitchen or living space downstairs and an extra bedroom or bathroom above.
How much does a double-storey extension cost in Houghton-Le-Spring?
In Houghton-Le-Spring, a double-storey extension typically costs £1,500–£2,250 per m² of floor area (both floors), including VAT at 20% (standard rate). For a typical 36 m² project that is roughly £54,000–£81,000. That range is adjusted for the North East, where domestic building work typically costs around 10% below the national average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (25 m²) | £37,500–£56,000 |
| Typical project (36 m²) | £54,000–£81,000 |
| Larger project (50 m²) | £75,000–£112,500 |
| Rate per m² | £1,500–£2,250 |
Your quote will depend mainly on:
- Scaffolding and access to the rear
- Roof design and how it joins the existing roof
- Brick matching and external finishes
- Total floor area across both floors
Your exact price depends on the survey and drawings. The guide price tool gives a quick range in the meantime.
Do you need planning permission for a double-storey extension in Houghton-Le-Spring?
Here is how the rules work for a double-storey extension in England. In England an extension of more than one storey can only be permitted development at the rear, no more than 3 metres deep and at least 7 metres from the rear boundary, with matching materials and any upper side windows obscure-glazed. Most double-storey extensions therefore go through a householder planning application.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served before work starts.
If the answer is not clear-cut, we can apply for formal confirmation before you commit to the build.
What we handle
What we take care of:
- Opening up at both levels with steel beams
- Building control sign-off
- Windows, doors and staircase alterations
- Design drawings and planning application
- Brick or block walls, floors and a roof tied into the house
- Electrics, heating, plumbing and plastering
How long does it take?
Allow 14 to 20 weeks on site, after planning and building control approval. Allow time beforehand for drawings and approvals, usually 3 to 4 months.
Building in Houghton-Le-Spring
Across the North East, colliery-era terraces and newer estates sit side by side, so the right project depends on the house type.
Houghton-Le-Spring sits in Tyne and Wear, about 11 miles south-east of Newcastle upon Tyne. We cover the whole of Houghton-Le-Spring, including postcodes DH4.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about double-storey extensions in Houghton-Le-Spring
Will the first floor need a new staircase?
Not normally. The new rooms are reached from the existing landing, though a doorway or short corridor may need to be formed.
Does a double-storey extension need planning permission?
Usually. In England a two-storey rear extension can only be permitted development if it is no more than 3 metres deep and at least 7 metres from the rear boundary, and side extensions over one storey always need permission. In practice most are approved through a planning application.
How much does a double-storey extension cost in Houghton-Le-Spring?
In Houghton-Le-Spring, a double-storey extension typically costs £1,500–£2,250 per m² of floor area (both floors), including VAT at 20% (standard rate). A typical 36 m² project comes to roughly £54,000–£81,000. Your fixed price depends on the survey and drawings.
How long does a double-storey extension take in Houghton-Le-Spring?
Typically 14 to 20 weeks on site, after planning and building control approval. Design and approvals beforehand usually take 3 to 4 months.
How close can it be to my neighbour?
Councils look at loss of light and outlook for neighbours. Many apply a 45-degree guideline from the nearest neighbouring window. We design to the council’s published guidance to give the application the best chance.
